Field of Invention
The present invention relates to a memory system and a method of operating the same. More specifically, the present invention relates to a memory system capable of improving operation speed and a method of operating the same.
Discussion of Related Art
As large volume files such as music and moving images are used in portable electronic devices, the portable electronic devices are requiring memory systems with large storage volume. Memory systems include a plurality of memory devices to increase storage capacity. In memory systems including a plurality of memory devices, fast operation speed as well as large storage capacity are important characteristics.
The plurality of memory devices included in memory systems may be embodied using semiconductors such as silicon (Si), germanium (Ge), gallium arsenide (GaAs), and indium phosphide (InP). Semiconductor memory devices are generally classified into volatile and nonvolatile memory devices.
When the supply of electric power to volatile memory is cut off, data stored in the volatile memory disappears. Volatile memory devices include static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), and the like. On the other hand, when the supply of electric power to nonvolatile memory devices is cut off, data stored in nonvolatile memory devices is maintained. Nonvolatile memory devices include read only memory (ROM), programmable ROM (PROM), erasable programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM), flash memory, phase-change RAM (PRAM), magnetoresistive RAM (MRAM), resistive RAM (RRAM), ferroelectric RAM (FRAM), and the like. Flash memory may be further classified into NOR type and NAND type.
A plurality of semiconductor memory devices may be connected to a controller configured to control the semiconductor memory devices through a plurality of channels, and thus the controller selects and accesses the plurality of semiconductor memory devices at the same time. However, the above multi-channel access method is not applicable to semiconductor memory devices which are accessed through only one channel. When using only one channel in a real system, not a test environment, channels other than the selected channel are not used, and thus, operation speed may be slowed.